One of the guiding mottos of my work in data visualization is “eloquence through simplicity”—eloquence of communication through simplicity of design. I share this goal with many designers, present and past. Leonardo da Vinci once wrote: “Simplicity is the ultimate sophistication.” Unfortunately, people sometimes misunderstand what we mean by simplicity, assuming that simplification is a pitched battle against complexity, striving to eliminate it. In fact, thoughtful simplification preserves useful complexity and makes it easier to manage by reducing it to its essence.

I was prompted to write on this topic while reading Donald Norman’s latest book, Living with Complexity. Norman is a brilliant designer, whose work has helped to shape me, but in the midst of many gems of insight in this book, some of his ideas about simplicity and complexity struck me as logically flawed, especially the following:

Simplicity is not the opposite of complexity: complexity is a fact of the world, whereas simplicity is in the mind. (p. 53)

Did I read correctly? Complexity is a fact of the world but simplicity is not? There are things in the world that are actually complex but none that are actually simple? Simplicity is in the mind (i.e., a matter of perception) but complexity is not? We might perceive something that is complex as simple, but never the opposite? Does this make sense? To me, it doesn’t. Nothing about simplicity and complexity requires Norman’s distinction.

Although simplicity and complexity are not in conflict with one another, they are indeed opposites in that they are two poles of a continuum—the more complex something seems the less simple it seems, and vice versa. They describe our perceptions of and interactions with things that we encounter in the world. All that we encounter falls somewhere along this continuum as experienced from a particular perspective and engaged for a particular purpose. Our understanding of something, whether simple or complex, is in our minds, a matter of perception; our interaction with something, whether simple or complex, is determined by our abilities.

The closest that we can come to declaring some things as simple or complex in and of themselves is rooted in the fact that things are composed of parts or units—the fewer the simpler. In this sense, the more units that combine to form what we perceive as a thing in the world (a product, process, system, etc.), the more complex it is. The idea that simplicity or complexity resides in the thing itself, something that can be objectively measured, and not in our perception of it, falls apart, however, because there exists no single correct way to draw the lines that break something into its parts. This is a matter of perception. Things that seem simplest are those that we perceive as a single conceptual unit. The more conceptual units that must be combined to form a whole, the more complex we perceive the thing to be. In other words, the only useful way to frame simplicity and complexity is as a continuum of perception, not as facts of the world.

Through experience and learning, things that we once perceived as complex become perceived as progressively simpler. We tame complexity by breaking something down into the simpler conceptual units of which it is composed, while working to understand how they relate to one another. Through experience (practice, practice, practice), we combine these simpler units into progressively larger chunks, which we learn to hold in our minds and memory as single conceptual units. These mental constructs are called “conceptual models” or “mental models.” As a cognitive psychologist, Norman has done a great deal to help the world of design understand the role of conceptual models.

When I preach the glories of simplicity, I’m not saying that complexity is bad or that it should be ignored or eliminated. Much of what we face in the world seems complex. Much that is valuable seems complex. Complexity can be a source of incredible enjoyment; grappling with it can be a delightful form of play. We seek to understand complexity, co-exist with it, and make use of it by taming it. We do so by representing it as simply as possible without sacrificing what’s essential and useful. We do so in part by removing all that is extraneous to the thing by paring it down to its essence in relation to a particular goal.

When working with information to understand and communicate it—the focus of my work—I strive to represent it simply by removing what’s not essential, but to never oversimplify. In so doing, I hope to make complexity manageable, refusing to let it become unnecessarily complicated.

By paring information down to its essence, relative to our goals, we can make a great deal of information manageable. This is especially true of dashboard displays: single screens of information that people monitor to maintain the situation awareness that enables them to do their jobs effectively. Most of the dashboards that exist in the world fail because, by including so much that is extraneous to the information that’s needed, relatively little information can be meaningfully displayed. Screen real estate is wasted by filling it with visual content that isn’t information, and the viewer’s attention is distracted by this fluff from the little information that’s actually there. When properly designed, however, perceived complexity can be tamed, making it possible for a dashboard to display a dense and rich collection of information. Airline pilots learn to manage a huge amount of information in cockpit displays, with practice, if the displays are well designed. This potential exists in dashboards and is made possible, not primarily by the wonders of technology, but by the effectiveness of the design.

Complexity is our friend. The more complexity we learn to manage, the greater our knowledge and abilities become. Complex information is definitely our friend. It’s time we learned to tame it.

11 Comments on “Simplicity vs. Complexity: Design Goals”

By Keith Suckling.
January 10th, 2011 at 3:42 pm

I can just see the look on my boss’s face when I tell them that the thing itself isn’t simple or complex – it’s their abilities that make it so…
More likely the pressure for a fast to read headline will override the exploratory desire to understand and learn from the complexity.
– But that means I still have a job digging :-)

By David Leppik.
January 11th, 2011 at 1:18 pm

As a software developer, I divide things into two categories: accidental complexity, and necessary complexity. The former is the bane of my existence. Here’s a non-programming example of the difference. If you have 2-way traffic on roads, cars need to drive on the left or the right. Whichever side it is, that’s a necessary detail and drivers need to know it. However, the fact that in some countries you drive on the left and on others you drive on the right is accidental complexity. Having two standards is unnecessary and confusing.

I agree that complexity and simplicity are psychological; there are some programming languages (e.g. Lisp) which have a very simple grammar, but feel more complicated because of their simplicity. Binary numbers are very simple, but once you learn your addition tables, 10+13 looks much simpler than 1010+1101. There’s a sweet spot in there: a base-60 number system (like the Babylonians had) makes for very compact calculations, but I wouldn’t want to memorize the addition tables.

With data visualization, I see the same issues at play. You want the display to appear as simple as possible (eliminate accidental complexity) while revealing as much complexity as possible (maximize necessary complexity). And sometimes you make a graph more complex but make it feel less complex when you organize it in a way that brings out conceptual simplicity– for example, a map of the United States is graphically complex, but leverages the viewer’s geographical knowledge.

By Chris Pudney.
January 11th, 2011 at 5:53 pm

By coincidence the very next blog posting I read provides I concrete example of “eloquence through simplicity”.

You extended my position eloquently. Thanks for weighing in. (Note: What you call “accidental complexity”, Donald Norman calls “complication.” I prefer your term, however, because it speaks for itself.)

By Jan Fabry.
January 12th, 2011 at 8:48 am

I probably misunderstood both you and Donald Norman, I don’t see much difference between your interpretation and Norman’s. The distinction I think he makes is that something can be complex or not. But separate from that, our mental model of it can make it appear simple or not.

In this thinking there is no axis going from simple to complex, but they are two separate axes, which gives us complex situations visualized in non-simple ways (bad dashboards), but also complex situations visualized in simple ways (good dashboards). There are also non-complex situations explained in simple ways (what we would expect), and non-complex situations explained in non-simple ways (when hidden under jargon or other obfuscation techniques).

By Marty Gierke.
January 12th, 2011 at 3:52 pm

I would offer that Shaker furniture and architecture exemplifies a good balance of necessary and accidental complexity, and it’s the balance – not the absence of either – that communicates purpose, function and simplicity. Purity of expression is hard, and Buckminster Fuller was on to something when he said: “You uncover what is when you get rid of what isn’t.”

By Stella Lau.
January 26th, 2011 at 5:21 pm

Thanks for sharing this insightful post. I love the phrase “eloquence through simplicity.” I agree that the word “simple” by itself can lessen the value of information, even if the intention is to make it more attractive. In a world where information is abundant, it is more important than ever to be able to cut through the fog of information quickly and accurately. Your use of the phrase really drives this home. I truly believe that presenting information or data the way people need it, whether it’s in the form of dashboards or graphs, will help people to easily navigate through what they think is complex.

By Marc Gedansky.
January 27th, 2011 at 3:41 pm

Stephen –

Your article immediately reminded me of the famous Antoine de Saint-Exupery quote: “Perfection is achieved, not when there is nothing more to add, but when there is nothing left to take away.”

By led signs company.
February 9th, 2011 at 8:28 pm

We get where we will get because of hard work. Whether we choose to make that complex or simple is entirely up to ourselves and no-one else. I try to make my business life as simple as possible, because inevitably outside factors will bring complexity to it.

By janet grennell.
May 3rd, 2011 at 1:20 pm

What, then, are we to make of elegance? Is that the process of making the complex simple?

By Stephen Few.
May 4th, 2011 at 12:12 pm

Janet,

It depends on what you mean by “elegance.” I tend to use the terms “eloquence” and “elegance” in a related manner. I think of eloquence as elegant communication. By elegance in the context of design, I tend to mean a design that does what’s intended so exceedingly well, it functions beautifully. So yes, to me making something that is complex as simple as possible without sacrificing useful complexity is an example of elegance.